Sigma is rumored to announce a new 24-70mm f/2.8 Mark II lens next week (May 16): What’s next? Related posts: Here are the upcoming Sigma 500mm f/5.6 DG DN OS Sports & Sigma 15mm f/1.4 DG DN Diagonal Fisheye Art lenses (full specs and pictures) What’s next? What’s coming next? The latest patents Sig...